Waves Plugins Show up Temporarily then Disappear

Thank you for reading!

I have recently installed the version 9 Waves Mercury package from an offline installer, that was saved to an external hard drive. On the first attempt, they all failed to validate, and I eventually deleted all the files from every conceivable location, and re-installed. Everything seemed to work just fine, and the plugins all appear in Plugin Manager, although they all say "couldn't be opened" but I have been selecting the ones I need and individually, and running the "Reset and Rescan Selection". After which they say "Successfully Validated" and show up/function normally in the Audio Effects Channel strip. But ONLY until I close Logic. When I reopen the song, I get a message saying "The plug-in named "CLA Vocals" isn't available on your system. Choose another plug-in, or quit Logic Pro X and install the plug-in on your computer in order to use it in the project."

But since they work at first, I think it's some kind of issue with Logic/Apple not trusting them etc... Any ideas?

I have contacted Waves support but I dont really get anywhere and they want to charge me to update to the latest version, which I dont want or need.

Any help would be GREATLY appreciated! Thank you.